Method of manufacturing a semiconductor package using lead frame having through holes or hollows therein

Abstract

A lead frame comprises a stage for mounting a semiconductor chip thereon, a plurality of leads arranged in the periphery of the stage, and a plurality of lead interconnection members (e.g., dam bars) for interconnecting the leads, wherein a plurality of through holes are formed to penetrate through the lead frame in a thickness direction with respect to the leads or the lead interconnection members so as to allow a plurality of cutting lines to pass therethrough, whereby the leads are subjected to cutting and are made electrically independent of each other. A semiconductor package of a QFN type is produced by enclosing the lead frame within a molded resin, from which the leads are partially exposed to the exterior and are subjected to plating and are then subjected to cutting at the cutting lines.

1 . A lead frame comprising: 
 a stage for mounting a semiconductor chip thereon;    a plurality of groups of leads arranged in a periphery of the stage;    a plurality of lead interconnection members for interconnecting a plurality of leads in each group of the leads respectively; and    a hollow that is formed to concave in a thickness direction on each lead, thus allowing a plurality of cutting lines to pass therethrough,    wherein the plurality of lead interconnection members and the plurality of leads are subjected to cutting at the cutting lines so that the plurality of leads are made electrically independent of each other.    
   
   
       2 . The lead frame according to  claim 1 , wherein the hollow is replaced with a through hole.  
   
   
       3 . A lead frame comprising: 
 a stage for mounting a semiconductor chip thereon;    a plurality of groups of leads arranged in a periphery of the stage;    a plurality of lead interconnection members for interconnecting a plurality of leads in each group of the leads respectively; and    a hollow that is formed to concave in a thickness direction on each lead interconnection member across the plurality of leads, thus allowing a plurality of cutting lines to pass therethrough,    wherein the plurality of lead interconnection members and the plurality of leads are subjected to cutting at the cutting lines so that the plurality of leads are made electrically independent of each other.    
   
   
       4 . The lead frame according to  claim 3 , wherein each of the leads has a projecting portion that is projected inwardly into the hollow.  
   
   
       5 . The lead frame according to  claim 3 , wherein the hollow is replaced with a through hole.  
   
   
       6 . A semiconductor package having a plurality of leads that are exposed to an exterior of a molded resin, wherein a side surface of the lead is associated with a plated surface and a cut surface that adjoins the plated surface and that makes the adjacent leads to be electrically independent of each other.  
   
   
       7 . The semiconductor package according to  claim 6 , wherein a backside of the lead subjected to plating is formed in a same plane together with a lower surface of the molded resin.